# NTSB CEN13LA523: Bell-Transworld Helicopter Cor 47G-2, N8051E, Wichita Falls, TX, August 28, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 28, 2013, 08:45 local (13:45 UTC) - Place: Wichita Falls, TX - Coordinates: 33.800571, -98.509719 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.8006&lon=-98.5097&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 23, 2014 - Report: Approved by Office Director - NTSB office: Central Region - NTSB case key (mKey): 87965 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN13LA523 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/87965/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=87965 - Page: https://openairdocs.org/ntsb/CEN13LA523 ## Probable cause The delayed remedial action by the flight instructor during a simulated autorotation, which resulted in a hard landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: descent rate](https://openairdocs.org/ntsb-findings/01062037): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-findings/01062037/cases.md?model=1181071), [All aircraft, 242 cases](https://openairdocs.org/ntsb-findings/01062037/cases.md) - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=1181071), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md) - [Experience/qualifications: total experience w/ equipment](https://openairdocs.org/ntsb-findings/02031025): Personnel issues › Experience/knowledge · Student/instructed pilot; cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-findings/02031025/cases.md?model=1181071), [All aircraft, 269 cases](https://openairdocs.org/ntsb-findings/02031025/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Autorotation: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=1181071), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Uncontrolled descent: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=1181071), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092) (defining event); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-events/092/sequence.md?model=1181071), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Bell-Transworld Helicopter Cor 47G-2, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=1181071), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis After the flight instructor initiated a simulated autorotation during an instructional flight, he instructed the student pilot to perform a power recovery. However, the student pilot delayed increasing the power, and the rotor rpm decayed. The flight instructor realized that it was too late to make a full recovery, so he took the flight controls and leveled the helicopter for touchdown and pulled the collective. The helicopter landed hard in a soft field, which resulted in damage to the tail rotor and main rotor blades. The flight instructor stated that he deviated from his normal procedure for recovery from a simulated forced landing and that, if he had used the procedure, the accident may not have happened. ## Factual narrative On August 28, 2013, at 0845 central daylight time, a Bell-Transworld Helicopter Corp. 47G-2, N8051E, impacted terrain during a simulated autorotation to a field near Wichita Falls, Texas. The helicopter received substantial damage to the main rotor blades. The flight instructor and student pilot were uninjured. The helicopter was registered to and operated by the student pilot under 14 Code of Federal Regulations Part 91 as an instructional flight that was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The flight originated from Wichita Falls, Texas, about 0830. According to the National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report that was received from the flight instructor, he and the student pilot departed from the student's hangar area for an instructional flight. Upon climbing to 500 feet above ground level, they flew to a private airstrip called Danaher, which was near the southwest end of Lake Wichita. After a normal approach and hovering practice, they flew toward the west to a small pinnacle to practice landings. At 500 feet above ground level, over a clear area, they initiated a simulated forced landing. The flight instructor reduced the throttle and announced a forced landing and that the student was to perform a power recovery. The flight instructor realized that it was too late to make a full recovery, and he leveled the helicopter for touchdown and pulled collective. The touchdown was slightly tail low, and the ground was soft and level. The full fuel load caused the skid heels to sink a few inches causing the tail rotor guard to break, allowing the tail rotor blades to contact the ground. The tail rotor guard contacted and damaged both main rotor blades. The flight instructor stated he deviated from his normal procedure for recovery from a simulated forced landing. That procedure was: 1. After lowering the engine rpm and announcing forced landing. 2. Ensuring collective is in full down position and rotor rpm was stable and in the green arc. 3. Return engine rpm to a near operating rpm. 4. Ensure that the airspeed for autorotations is established and maintained to landing flare. The student pilot held a private pilot certificate with an airplane single-engine land rating. He accumulated a total flight time of about 330 hours, of which 269 hours were in single-engine airplanes and 61 hours were in rotorcraft. The 61 hours of rotorcraft were all in the make and model of the accident helicopter. ## Aircraft - Registration: [N8051E](https://openairdocs.org/aircraft/N8051E), registered now, S/N TWH-15 (OpenAirDocs) - Reported make and model: BELL-TRANSWORLD HELICOPTER COR 47G-2 - Registry model: [Bell-Transworld Helicopter Cor 47G-2](https://openairdocs.org/model/bell-transworld-helicopter-cor-47g-2) (registry code 1181071) (OpenAirDocs) - Registry engine: [Lycoming VO-435-A1D](https://openairdocs.org/engine/lycoming-vo-435-a1d) (registry code 42198, reciprocating) (OpenAirDocs) - Category: Helicopter - Serial number: TWH-15 - Year built: 1979 - Airframe hours: 2665 - Engines: Lycoming VO435A1F 265 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, July 8, 2013 - Departed: PVT, Wichita Falls, TX - Destination: Wichita Falls, TX ## Flight crew As NTSB recorded them. NTSB leaves out names. - Flight instructor; age 77; injuries: none; flight engineer, commercial; airplane ratings: single-engine land; instrument ratings: airplane, helicopter; medical: class 3, with waivers/limitations; last flight review July 10, 2012; seat: right; restraint: lap only; flight hours: 7,500 total, 500 in this make and model, 7,200 as pilot in command, 40 in the last 90 days, 20 in the last 30 days, 2 in the last 24 hours - Student pilot; age 66; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review October 10, 2012; seat: left; restraint: lap only; flight hours: 330 total, 61 in this make and model, 221 as pilot in command, 21 in the last 90 days, 13 in the last 30 days, 2 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 75 °F, dew point 68 °F - Altimeter: 30.10 inHg - Observed at: CWC, 4 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20130828018289A](https://openairdocs.org/incident/20130828018289A), Aug 28, 2013: Bell-Transworld Helicopter Cor 47G-2, Wichita Falls, TX, Substantial damage. On August 28, 2013, at 08:45 central daylight time, a Bell-Transworld helicopter corp., N8051E, model 47G-2, impacted terrain during a simulated autorotation… ## Docket (1 files) The files NTSB released with the investigation on December 20, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=87965. 2.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40405764&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.